Torque sensors for detection of a torque acting around a rotation axis are widely used in various kinds of transport equipment and industrial apparatuses. For example, the below-listed Patent Literature 1 discloses a sensor that, by using a strain gauge to detect strain occurring in a ring-shaped load detection mechanism, detects an operating force component and a moment component as electrical signals. Further, Patent Literature 2 discloses a sensor that detects as electrical signals an operating force component and a moment component by detection of strain occurring in radial direction components arranged between a rigid central component and a rigid circular ring.
Further, Patent Literature 3 discloses a sensor that detects as an electrical signal a torque acting around a rotation axis, by using capacitor elements to detect elastic deformation of a detection ring that has a through-hole through which a rotation shaft is inserted, and by supporting the detection ring via a support member from either side along the rotation shaft. Further, Patent Literature 4 discloses a sensor capable of adjusting balance of detection sensitivity between force and moment while securing an internal space, by adopting a structure that arranges multiple detection rings adjacent to one another.